When is the last frost in Sula, MT?

Frost is possible in any month at the nearest NOAA station (Wisdom, MT), so there is no reliable average last frost date.

When is the first frost in Sula, MT?

Frost is possible in any month at the nearest NOAA station.

Are these frost dates a forecast?

No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.

Frost dates for 59871Sula, MT

Frost is possible in any month near Sula, based on NOAA 1991-2020 records for the Wisdom, MT station.

Frost is possible in any month. Even summer nights can drop to freezing at this station, so protect tender plants whenever cold nights are forecast.

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
Temperature	Last spring: 90% / 50% / 10% chance	First fall: 10% / 50% / 90% chance	Growing season (50%)	Years with at least one
Light frost (36°F)	—	—	10 days	100%
Frost / freeze (32°F)	—	—	22 days	100%
Hard freeze (28°F)	—	—	48 days	100%

Where these dates come from

ZIP code 59871 is matched to the NOAA station Wisdom, MT, 41.3 km away, at 6,060 ft elevation (69 ft lower than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
Wisdom, MT (used)	6,060 ft	—	—
Sula 3 Ene, MT	4,475 ft	—	—
Sula 14 Ne, MT	5,155 ft	—	—
Darby, MT	3,880 ft	May 24	Sep 23

Frost dates near Sula

Conner, MT 59827 · last —, first —
Gibbonsville, ID 83463 · last —, first —
Darby, MT 59829 · last May 24, first Sep 23
Wisdom, MT 59761 · last —, first —
Grantsdale, MT 59835 · last May 21, first Sep 22
North Fork, ID 83466 · last —, first —
Hamilton, MT 59840 · last May 21, first Sep 22
Corvallis, MT 59828 · last May 23, first Sep 21

Frequently asked questions

When is the last frost in Sula, MT?: Frost is possible in any month at the nearest NOAA station (Wisdom, MT), so there is no reliable average last frost date.
When is the first frost in Sula, MT?: Frost is possible in any month at the nearest NOAA station.
Are these frost dates a forecast?: No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.